Method of producing two pipe connections from a single forging

ABSTRACT

A novel and relatively inexpensive process is provided for making high quality metallic connector members for metal conduits, pipes, pressure vessels, etc. the same frequently weighing, for example, between approximately 1376 pounds and approximately 138 pounds; the process being characterized by the initial and practically simultaneous rough-forming of a pair of connector members which is subsequently split, and the split articles then subjected to further processing. The pair of connector members so formed may be of entirely conventional configuration, such as a commonplace Tee connector, for example, or, in the alternative, of a unique conformation which possesses certain advantages in that the base or plate element is substantially rectangular with peripheral edges, for connection with the corresponding edges of the opening formed in the conduit or pressure vessel, which are formed along lines that are substantially straight, and for this reason alone are much easier to line-up and weld into position by either hand or machine welding, as compared with prior art practices which, for the most part involve peripheral edges to be lined-up and welded that delineate oval or saddle shapes. This rough-forming of a pair of connector members (to be followed by additional operations to obtain two finished connector members) is performed on a (heated) work-piece wherein the areas of displacement are of such size as to permit the same to be used over a wide variety of sizes of finished connector members, as distinguished from the prior art methods of flueing from a flat plate or drop-forging wherein only one finished size is obtainable, which makes it necessary to maintain a very large stock of die sizes.

llite States atent [19 Moore Aug. 27, 1974 METHOD OF PRODUCING TWO PIPE CONNECTIONS FROM A SINGLE FORGING [76] Inventor: Charles H. Moore, 645 Matanzas Ct., Fort Myers Beach,-Fla. 33931 22 Filed: July 20,1973

21 Appl. No.: 381,095

[52] US. Cl. 72/340, 29/157 T, 72/364, 72/368, 72/370 [51] Int. Cl B2ld 28/00 [58] Field of Search ..29/157.1 R, 157 R, 157 T, 29/412, 417, 557, 558; 72/340, 254, 255, 256, 358, 368, 364, 370

Primary ExaminerCharles W. Lanham Assistant ExaminerJames R. Duzan [57] ABSTRACT A novel and relatively inexpensive process is provided for making high quality metallic connector members for metal conduits, pipes, pressure vessels, etc. the same frequently weighing, for example, between approximately 1376 pounds and approximately 138 pounds; the process being characterized by the initial and practically simultaneous rough-forming of a pair of connector members which is subsequently split, and the split articles then subjected to further processing. The pair of connector members so formed may be of entirely conventional configuration, such as a commonplace Tee connector, for example, or, in the alternative, of a unique conformation which possesses certain advantages in that the base or plate element is substantially rectangular with peripheral edges, for connection with the corresponding edges of the open- 7 ing formed in the conduit or pressure vessel, which are formed along lines that are substantially straight, and for this reason alone are much easier to line-up and weld into position by either hand or machine welding,

as compared with prior art practices which, for the most part involve peripheral edges to be lined-up and welded that delineate oval or saddle shapes. This rough-forming of a pair of connector members (to be followed by additional operations to obtain two finished connector members) is performed on a (heated) work-piece wherein the areas of displacement are of such size as to permit the same to be used over a wide variety of sizes of finished connector members, as distinguished from the prior art methods of flueing from a flat plate or drop-forging wherein only one finished size is obtainable, which makes it necessary to maintain a very large stock of die sizes.

12 Claims, 8 Drawing Figures Pmmzmzmu q 3,831,422

smears Fig. 4

METHOD OF PRODUCING TWO PIPE CONNECTIONS FROM A SINGLE FORGING Metallic connector members of the type comprehended by the teachings of the present invention are frequently used to form branch outlets at openings in the walls of metal conduits, pipes, cylindrical pressure vessels and the like; for example, at outlet openings in the walls of water, oil or gas transmission lines which operate under high pressures.

Although not limited thereto, the present invention will, for illustrative purposes, hereinafter be described as applying to a T pipe fitting which comprises a large base element for insertion into a suitable opening in a line pipe and a relatively centrally disposed outlet or branch element of smaller. diameter.

It is, of course, widely known that the patent art to which the present invention relates, is voluminous and fairly highly developed; mainly due to the fact that both the articles which are produced and the equipment for producing them are heavy and somewhat cumbersome, and this is true of the apparatus for welding the connector members in the position of their usage.

Since connector members of the class to which the present invention relates are of such size as to average between approximately 1,376 pounds for a 24 inch X 20 inch T Schedule 160 and approximately 138 pounds in weight for a inch X 6 inch T Schedule 160 and the costs of dies and other equipment for forming and installing the same are so costly, producers tend toward reluctance in trying new processes and products whose efficiency has yet to be established.

For a number of years, T pipe fittings which possess a base that is oval or saddle-shaped have generally been considered as being the most practical for insertwelding into a correspondingly shaped opening in pipe line or pressure vessel, primarily because it appeared to require a minimum of welding, and the present invention is well adapted to produce the same.

However, the welding peripheries of saddle and oval shapes necessarily involve welding along lines which are curvilinear. The process of the present invention is also adapted to produce a connector member which is unique in that the base or plate element is substantially rectangular in order to cooperate with a correspondingly shaped opening in the periphery of the conduit or pressure vessel. Thus, both the line-up on insertion and the welding operation are conducted along substantially straight lines which are considerably easier to follow. The fact that the product of this invention is accurately machine bored adds ease to this fit-up, whereas the oval or circular fittings are not, and consequently they do not line-up with the inside of the line pipe as readily.

It is among the objects of the present invention to provide a process for less expensively manufacturing highly satisfactory connector members for metallic conduits, pressure vessels and the like, which are of conventional configuration, as well as produce a unique connector member which is of such configuration that it may be lined-up and installed with greater rapidity and economy.

Another object is the provision of a process for manufacturing connector members of the types referred to which includes a forging step that permits a displacement bore which is relatively heavy, and which results in minimum die expense and cost of product.

Another object is the provision of a process which can satisfactorily produce such connector members of a size wherein the branch or smaller outlet is of considerably smaller diameter than 12 inches, which has heretofore been considered the practical lower limit due to the height of the branches when manufacturing Tees by the widely used prior art methods which include the flueing of a metallic plate.

Still another object is to provide a process which not only achieves the objectives set forth hereinabove, but also permits the use of branch passages which are only one pipe size smaller, such as 12 inches X 10 inches, instead of the usual two-size ratio, i.e., 12 inches X 8 inches.

A further object is the provision of a process for manufacturing not only T pipe fittings and the like, but also laterals with outlet extending, for example, at 30 or 45.

A further object is the provision of a process for making connector members for the purposes stated which may possess two or more outlets or branches in each member to thus provide halves or segments which may later be assembled to make-up a header, manifold, etc.

A still further object is the provision of a process for manufacturing connector members which involves the use of die members that can readily produce desired reinforcement at appropriate places adjacent to the branches of the completed article by making provision therefor in the cavities of the die members for the reinforcement.

The foregoing and other objects and advantages will be more fully understood from the following description and annexed drawings, wherein like reference numerals refer to like parts, and wherein:

FIG. 1 is a plan view representing an assembled pair of opposed forging die segments which form part of an apparatus which may be employed to practice the process of the invention;

FIG. 2 is a sectional elevational view of a pair of forging die segments in assembled relationship with the heated work-piece to be forged disposed therewithin;

FIG. 3 is a view which is similar in nature to the view of FIG. 2, and the left side of FIG. 4 and illustrating the shape of the forged work-piece as the forging operation nears completion.

FIG. 4 is a composite view about a vertical centerline, and partly in section; illustrating to the left, the heated work-piece in position within the forging die preparatory to the forging operation, and with progressively smaller forging disc 22 and round stem metallic follower 23 disposed thereabove; and, on the righthand side of the vertical center-line, illustrating the forging disc 22 in a position which is approximately 3 inches above the bottom of the die cavity as the forging operation nears completion, and showing the forged metal displaced into the recesses or cavities of the die.

FIG. 5 is an elevational view of the right-hand side of the forged article with dimensions showing the changes which have taken place as the result of the forging operation, and prior to punching out the bottom and illustrating the manner in which the required shape and weight of the work-piece is determined preparatory to its being placed in the forging cavity.

FIG. 6 is a schematic view illustrating the manner of treating one of the forged segments, after the initial forging operations, which did not assume its intended dimensions.

FIG. 7 is a longitudinal sectional elevation illustrating a rectangular base member which communicates with two outlet members, one of which (A) is provided with an improved and substantially rectangular base plate and the other outlet member (B) having an oval base; both in position to be insert welded into the wall of a pipe or pressure vessel.

FIG. 8 is a sectional elevation illustrating the manner of employing the invention to produce a lateral instead of a connector Tee.

Referring more particularly to the drawings, in FIG. 1 the reference characters 2a and 2b designate a pair of exteriorly semi-circular segments which, when assembled in opposed relationship form a vertically extending forging die comprising a die cavity having a longitudinal axis 3 from which arcs are based that form relatively short upper and lower cylindrical walls 5 and 6, respectively.

The central or main portion of the die cavity comprises a pair of oppositely disposed relatively long and fairly deep die cavities 7 which extend at right-angles to the longitudinal axis 3 of the forging die 2a-2b; said die cavities 7 resulting in the formation of frustoconical bosses of relatively large diameter which extend at right-angles to said axis 3. These frusto-conical bosses of the forging which are formed in the die cavities 7 are flat on their outer ends, as indicated at 8, and after processing, form the branch pipe outlets of a pair of back-to-back connector members.

The inner and circular base of each of these frustoconical bosses is formed by a continuous fillet 12 which connects with the aforementioned relatively short cylindrical walls 5 and 6 as viewed at the upper and lower ends of the die cavity shown in FIGS. 2 and 3.

The frusto-conical protuberances or bosses of the forged product are designated at 14; and as indicated hereinbefore, after further processing, i.e., boring, form the outlet or branch opening 16 of a connector member, which for illustrative purposes constitutes a connector Tee.

As shown in FIG. 2, the semi-circular exterior surfaces of the forging die segments 2a and 2b are provided with a taper for receiving a seamless metallic holding ring 18 which is correspondingly tapered on its inner surface. By driving the holding ring downwardly onto the correspondingly tapered exteriors of the semicircular die segments 2:: and 2b they may be suitably secured together during the forging operation. However, some forge shops are provided with oppositely disposed horizontal hydraulic rams for suitably positioning and securing opposed forging die segments on the bed of a forging press, and these may be employed with perhaps even greater facility.

The space provided between the opposing relatively short cylindrical wall 6 of the assembled forging die segments 20 and 2b receives a removable knife ring 3 with an equally removable round and solid plug 17 disposed therein, as will be later referred to in greater detail.

In the illustrative example of the present invention, the forging die segments 2a and 2b may be so shaped in the manner described earlier herein to provide a reducing Tee of 20 inches diameter and with a branch pipe or outlet opening which is 16 inches in diameter.

In such case the round work-piece, as indicated at 19 in FIG. 2 and the left side of FIG. 4, may acceptably be 20 inches in diameter.

After heating to suitable forging temperature, the round work-piece 19, which is shown as being of lesser height than the chamber of the composite forging die 2a-2b, is disposed in the mold cavity on top of the removable knife ring 30 and the plug 17 removably disposed therewithin; and a metallic forging disc 22 of several inches in thickness, and of a diameter which is slightly less than that of the inside diameter of Schedule 160 pipe (such as 15% inches) is centered on the workpiece, preparatory to initiating the first forging step.

An elongated round stem metallic follower 23 of slightly less diameter than the disposable metallic forging disc 22 (such as 15 inches) is centered on the forging disc 22 and is forced downwardly with respect thereto by the platen, or upper movable member, of the forging press, forcing disc 22 to within 3 inches of the bottom of the forging cavity and the removable cylindrical plug 17 and the knife ring 30 but no further at this stage of the operation.

Such a disposable metallic forging disc 22 as used with an elongated round stem metallic follower 23 are important features of the present invention, as well as in the invention disclosed and claimed in my copending Patent Application Ser. No. 329,962, filed Feb. 6, 1973 and entitled Process of Forging and Product Thereof.

During the forging operation as described up to this point, the center (15% inches) of the metal of the round and solid metallic work-piece 19 is displaced from the center thereof into the cavities in the inner surfaces of the opposed die segments 2a and 2b; all except the bottom 3 inches which is never used and which is eventually punched out through knife 30 with disposable disc 22 acting as the punch and motivated by the elongated round stem metallic follower 23, and the forging is back-extruded in height into the cylindrical chamber 5.

At this point, the composite forging die 20-2!) is raised, the round and solid plug 17 removed leaving circular knife 30 disposed around the bottom opening in the die cavity; and the remaining metal of 3 inch thickness, together with the expendable forging disc 22, are punched or forced completely out of the forging die from downward exertion on the round-stem follower 23; as represented in the right-hand portion of the composite view of FIG. 4.

After the forging operation, the seamless holding ring 18 is removed, the die segments 2a and 2b opened up, and the one-piece seamless forging removed.

The one-piece forging is next placed in a machine tool and a welding kerf machined on the ends of the forging which are of 20 inch diameter, and which were adjacent the upper and lower relatively short cylindrical sections 5 and 6 of the die.

The bore of the one-piece forging is then machined to appropriate diameter; such as 16.064 inches if the forging is to apply to Schedule 160 pipe, 16.5 inches if for Schedule 140 pipe, 17 inch diameter if for Schedule pipe, etc.

After the aforementioned operations, the one-piece forging is sawed or burned in half on the vertical center-line thus producing in the example described hereinbefore a pair of identical insert-type reducing Tees 20 inches with 16 inch branches, the bases or plate sections of which are substantially rectangular in plan.

The stright center-line edge of each of these two insert-type reducing Tees is planed or burned to provide a welding kerf; and the branch bore 16 of FIG. 1 is burned out and bored, the branches kerfed for welding, and the proper inside radius added for proper flow, of the liquid or gas to be conveyed.

In the event curvilinear welding surfaces are preferred for the edges of the plate section, they may easily be shaped by burning at the forge shop, or in the field, thus providing a circular or oval insert saddle.

If, after the splitting operation to separate the roughforging into two parts, it is observed that, contrary to expectation, the die cavities l4l4 have not been completely filled with displaced metal of the workpiece the two rough-forged segments are re-heated to forging temperature, replaced in their respective die segments (2a-2b) and then one-at-a-time placed on the bed or table of the forging press: in horizontal position with the rough-forging face-up, as shown in FIG. 6.

A round forging tool 1 is centered on the inner surface of that portion of the solid boss-portion of the rough-forging where the branch connection of the connector member is later to be made as also shown in FIG. 6.

The round forging tool 1 should be of lesser diameter than the hole which is to be machined for the passageways 16 for the branch connections.

With the round forging tool I placed in the position aforementioned, and with the aid of a follower 2 and the platen of the press, the forging tool 1 is made to force or forge-out the metal C into the heretofore unfilled areas A and B, which previously may not have filled completely.

After the operation described immediately hereinbefore, the two rough-forged segments, or halves, are matched and tack-welded together; and the process continued in the same manner as earlier described, insofar as machining etc. is concerned.

In FIG. 8 there is shown a modified form of the invention as comprising die segments 20 and 2d for producing an identical pair of connector members of the type known as laterals; in this instance branch pipe connections which extend at approximately 45 to 30 with respect to the longitudinal axis of the chamber of the forging die, the passageways for the branch connections being indicated at 16a.

According to this embodiment, the segments 2c and 2d are shaped on their interior surfaces to provide die cavities which are modified to the extent shown in lieu of those which were described earlier herein in connection with the segments 2a and 2b for providing the bosses or protuberances which are to form the branches or outlets 16a of a lateral.

As stated earlier herein, the dimensions of FIG. 5 illustrate the manner in which the desired initial shape and weight of the work-piece 19 are developed.

The outside diameter of the cylindrical work-piece preparatory to forging is indicated as being 20 inches; the inside diameter during the forging operation has inches; the interior of the forging, not including the 3-inch thick remainder at the bottom thereof, is 23 inches in height. This portion of the forging, which does not include the 3-inch thick remainder at the bottom thereof, weighs 777 pounds. The bottom portion of 3- inch thickness and 20 inches in diameter weighs 267 pounds. When in the proportions shown in FIG. 5, the metal of the two solid opposed bosses 35 (for the branch pipe or outlet openings to be subsequently formed therein) together weigh 643 pounds.

Thus, the foregoing requirements of 777 pounds 267 pounds 243 pounds Total I687 pounds For a cylinder of 20-inch diameter this 1,687 pound weight of the steel to be forged requires a starting height of 18.95 inches; and due to the combination of forward extrusion and back-extrusion effected by the throw-away forging disc 22, the completely forged article becomes 26 inches in height.

Other shapes for providing connector members for the purposes described herein are within the contemplation of the invention, the'essential feature, however, being a forged unitary work-piece which is symmetrical on both sides and which is later split in half.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent is:

1. The process of producing in unison a pair of metallic connector members for metal conduits, pipes, cylindrical pressure vessels and the like which includes a. providing a pair of substantially identical exteriorly semi-cylindrical forging die segments each possessing die recesses on their inner surfaces which include relatively short cylindrical sections adjacent their ends and a substantially deeper and substantially longer intermediate section which is connected thereto through fillets b. assembling the hereinbefore described forging die segments with their respective die recesses in opposed relationship, and securing the same against separation c. placing within the forging cavity provided between the die recesses of the opposed die segments a cylindrical work-piece having a diameter which is slightly less than the space between the relatively short cylindrical sections adjacent the ends thereof,

which is of substantially lesser length than the forging cavity, and which has been heated to forging temperature (1. placing atop the aforementioned work-piece a relatively thin metallic disc of slightly less diameter than the work-piece e. applying to the top of the relatively thin metallic disc an elongate round forging member which is of slightly less diameter, but which is of greater length than the forging cavity f. downwardly moving elongate round forging member against the relatively thin metallic disc until the metal of the heated work-piece has been made to flow into at least the majority of the areas of the die recesses of the opposed forging die segments, the same including substantial backward extrusion and the substantial lengthening of the work-piece g. removing the opposed forging die segments h. longitudinally splitting the longitudinally bored forging into a pair of identical sections with centrally disposed bosses and i. forming a pair of complete metallic connector members from the halves of the initial forging, with bores in the centrally disposed bosses to provide branch passageways, and the remainder of the halves providing plate portions for insert-welding into correspondingly shaped openings in the element with which the branch passageways are to communicate.

2. The process of claim 1 wherein the bottom of the forging cavity is open but temporarily closed by a removable plug, and wherein the downward movement of the elongate round forging member against the relatively thin metallic disc is continued until the latter is adjacent to but spaced upwardly from the lower short cylindrical section of the forging chamber; then removing the removable plug, and continuing the aforementioned downward movement until the remaining metal of the work-piece and the relatively thin metallic disc are forced from the bottom of the die cavity.

3. The process of claim 1 wherein welding kerfs are machined onto the longitudinal ends of the forging and the longitudinal bore thereof is machined prior to the longitudinal splitting of the forging.

4. The process of claim 1 wherein the straight centerline of each of the halves is provided with a welding kerf, the ends of the bosses provided with welding kerfs, the bosses bored to provide the branch passageways, and the proper inside radius added; all after the longitudinal splitting of the initial forging.

5. The process of claim 1 wherein a Tee connection is produced.

6. The process of claim 2 wherein a Tee connection is produced.

7. The process of claim 3 wherein 21 Tee connection is produced.

8. The process of claim 4'wherein a Tee connection is produced.

9. The process of claim 1 wherein a lateral connection is produced.

10. The process of claim 2 wherein a lateral connection is produced.

11. The process of claim 3 wherein a lateral connection is produced.

12. The process of claim 4 wherein a lateral connec- 

1. The process of producing in unison a pair of metallic connector members for metal conduits, pipes, cylindrical pressure vessels and the like which includes a. providing a pair of substantially identical exteriorly semicylindrical forging die segments each possessing die recesses on their inner surfaces which include relatively short cylindrical sections adjacent their ends and a substantially deeper and substantially longer intermediate section which is connected thereto through fillets b. assembling the hereinbefore described forging die segments with their respective die recesses in opposed relationship, and securing the same against separation c. placing within the forging cavity provided between the die recesses of the opposed die segments a cylindrical work-piece having a diameter which is slightly less than the space between the relatively short cylindrical sections adjacent the ends thereof, which is of substantially lesser length than the forging cavity, and which has been heated to forging temperature d. placing atop the aforementioned work-piece a relatively thin metallic disc of slightly less diameter than the work-piece e. applying to the top of the relatively thin metallic disc an elongate round forging member which is of slightly less diameter, but which is of greater length than the forging cavity f. downwardly moving elongate round forging member against the relatively thin metallic disc until the metal of the heated work-piece has been made to flow into at least the majority of the areas of the die recesses of the opposed forging die segments, the same including substantial backward extrusion and the substantial lengthening of the work-piece g. removing the opposed forging die segments h. longitudinally splitting the longitudinally bored forging into a pair of identical sections with centrally disposed bosses and i. forming a pair of complete metallic connector members from the halves of the initial forging, with bores in the centrally disposed bosses to provide branch passageways, and the remainder of the halves providing plate portions for insertwelding into correspondingly shaped openings in the element with which the branch passageways are to communicate.
 2. The process of claim 1 wherein the bottom of the forging cavity is open but temporarily closed by a removable plug, and wherein the downward movement of the elongate round forging member against the relatively thin metallic disc is continued until the latter is adjacent to but spaced upwardly from the lower short cylindrical section of the forging chamber; then removing the removable plug, and continuing the aforementioned downward movement until the remaining metal of the work-piece and the relatively thin metallic disc are forced from the bottom of the die cavity.
 3. The process of claim 1 wherein welding kerfs are machined onto the longitudinal ends of the forging and the longitudinal bore thereof is machined prior to the longitudinal splitting of the forging.
 4. The process of claim 1 wherein the straight center-line of each of the halves is provided with a welding kerf, the ends of the bosses provided with welding kerfs, the bosses boRed to provide the branch passageways, and the proper inside radius added; all after the longitudinal splitting of the initial forging.
 5. The process of claim 1 wherein a Tee connection is produced.
 6. The process of claim 2 wherein a Tee connection is produced.
 7. The process of claim 3 wherein a Tee connection is produced.
 8. The process of claim 4 wherein a Tee connection is produced.
 9. The process of claim 1 wherein a lateral connection is produced.
 10. The process of claim 2 wherein a lateral connection is produced.
 11. The process of claim 3 wherein a lateral connection is produced.
 12. The process of claim 4 wherein a lateral connection is produced. 